There are two types of lymphomas - Hodgkin Lymphoma (Hodgkin`s Disease) and Non-Hodgkin Lymphoma. The follicular lymphoma belongs to the second group. It is a slow-growing B-cell lymphoma, and the second most common sub-type of NHL; most often occurs due to chromosomal translocation t(14;18) causing bcl-2 gene rearrangement. Most of the patients with FL are asymptomatic; hence they remain undiagnosed for years and usually detected in the advanced stages.

00:02
Our first major non-Hodgkin
lymphoma that we’ll take a look atwill be follicular lymphoma.
00:07
Let’s go straight to the point.
00:09
Where is the translocation
taking place in?14;18.
00:12
This 14;18 is then going
to over express BCL-2.
00:16
If we move on, BCL-2 is going to do what
with cytochrome C from the mitochondria?Our discussion, apoptosis,remember this is a cancer.
00:26
It will do everything in its power to
upregulate anti-apoptotic factors.
00:31
So therefore, BCL-2 if upregulatedprevents the release of cytochrome
C from the mitochondria.
00:37
You are not going to activate caspase
and you’ve inhibited apoptosis.
00:44
Causing increased survival
of your germinal center.
00:47
I’ll show you a picture in
which follicular lymphomain your lymph node in
non-Hodgkin’s lymphoma,a common one by the way,is involvement of your follicular,
follicular, portion of the lymph node.
01:02
And you’ll find this to be extremely,
extremely expanded and active.
01:07
And at some point in time, I
wish to mention here as wellthat 30 to 40% of time,
follicular lymphomamay actually then go on to
diffuse large B-cell lymphoma.
01:17
We’ll talk about different ways that
you will be responsible for developingdiffuse large B-cell
lymphoma for your boards.
01:24
One method might be from
follicular lymphoma.
01:27
If you find a diffuse large B-cell
lymphoma, having translocation 14;18,you know for a fact that it
came from follicular lymphoma.
01:38
The description of morphology in
follicular lymphoma in the lymph node,which is where the
problem began,you would find enlarged lymph nodeconsisting of small
cleaved lymphocytes.
01:52
If you would take a look at a lymph node
and here, it’s a lower amplification,you’ll find in the middle there
huge areas of the folliclethat are just about engrossing
this entire follicle.
02:06
Quite a bit of increase
in size of the follicle.
02:11
Upon closer examination,here once again, you’ll find in the middle
quite a bit of small cleaved lymphocytesin which you’ll find follicular
activity to be extremely prevalent.
02:25
This is follicular lymphoma
translocation 14;18.
02:28
Upregulation in BCL-2.
02:30
These cancer cells, these B cells
are going to remain alive forever.
02:36
Our topic here,an important differential is
the fact that you might havereactive lymphoid hyperplasia
versus follicular lymphoma.
02:46
The immunohistochemistry stain,at least be able to identify
what’s known as spectrin staining.
02:52
And your focus here,I’d like for you to take a look at would be
reactive type of your lymphoid hyperplasia.
02:59
Reactive.
03:00
Not a cancer per se.
03:02
So you would still have increased
activity of your folliclebased on the reaction that’s taking
place, maybe perhaps your infection.
03:10
Ands so therefore,how would you be able to differentiate
this from follicular lymphoma?Spectrin staining
would then help you.
03:19
And what you’re seeing here would be the
germinal center, which is quite active.
03:24
And you have an area,
that’s the mantle.
03:26
And then outside of this, you
then have your paracortex.
03:30
What you also would find is that,
well, stronger expression of spectrinand numerous tingible
body macrophages.
03:38
However, in the middle, do not, do not
appear to be take up your spectrin.
03:44
However, the T zone,
paracortex however will.
03:48
And this is quite important for you to
differentiate reactive lymphoid hyperplasiaversus what we’ll take a look
at with follicular lymphoma.
03:57
And follicular lymphoma,what you end up finding is going
to be positive spectrin stainingin what kind of cells?B-cells.
04:07
And B-cells are located where?In the follicle.
04:11
Let’s stop here and make sure
that you truly understandhow to differentiate reactive
lymphoid hyperplasiain which it’s responding to an invaderversus follicular lymphoma,
which is going to be a cancer.
04:26
If you remember correctly, if
it’s an acute type of reaction,the paracortex is going
to come and playand it’s going to start
activating, well, T-cells.
04:36
And you need CD4 and you need CD8.
04:38
And because of this, the spectrin
will be taken up by the T-cellsand therefore, the anatomy of the
lymph node now comes in handy.
04:46
Your T-cells reside where
in your lymph node?Paracortex.
04:51
Next, if you’re thinking
about follicular lymphoma,what kind of lymphoma is this?A non-Hodgkin’s lymphoma of the follicleand what kind of
cells are involved?B cells.
05:03
So now the B-cells are going to
start taking up your spectrin.
05:07
You’d expect this to occur in your
follicle as you’ll see in the picture.
05:15
A few more words about
follicular lymphoma.
05:18
It is a common non-Hodgkin’s lymphoma,it usually presents in middle
age and fairly indolentand average survival
age of eight years.
05:29
Chemotherapy works quite well
and as I mentioned earlier,about 30 to 50% of your patients
who have a translocation 14;18may then go onto diffuse
aggressive large B-cell lymphoma.
05:45
Therefore, if you find diffuse large B cell
lymphoma as being your morphologic pictureand they’re giving you
translocation 14;18.
05:54
It came from
follicular lymphoma.
05:58
A possible cause.
05:59
We’ll talk about two more
when the time is right.
06:03
This is not equivalent
to Richter syndrome.
06:06
When we talk about chronic
lymphocytic leukemia,the oldest of all the leukemias
in terms of your age group.
06:15
With CLL,there’s a fixed population
or small populationin which that CLL goes on to become
diffuse large B-cell lymphoma.
06:29
That is going to be
your Richter syndrome.
06:34
So right off the bat,I’m giving you two major possibilities of
developing diffuse large B-cell lymphoma.
06:43
Number one here,you’d focus upon follicular lymphoma
and when we discuss together CLL,at that point, I will
mention Richter syndrome.
06:53
And finally,I will refer to de novo type of development
of your diffuse large B-cell lymphoma.

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